Do you still have an HTC G1 lying around that you refuse to abandon? While both AOSP ICS and Jelly Bean based CM10 have been ported to run on the first Android device ever, neither are fast or stable enough for use as daily drivers. Thus, many still using this device are running Gingerbread, often themed to look like Ice Cream Sandwich or Jelly Bean through the use of custom launchers, themes, and fonts.
One UI element that has remained relatively unchanged is the lock screen. This is no longer the case, thanks to XDA Member HTCDreamOn, who has themed the stock pattern lock screen of the device to give it the ICS look. This mod requires the use of some basic tools such as Ninjamorph and a decent file manager.
Those looking to get started can find all the relevant instructions in the original thread.___________________